Design, Implementation, and Validation of a New Class of Interface Circuits for Latency-Insensitive Design

With the arrival of nanometer technologies wire delays are no longer negligible with respect to gate delays, and timing-closure becomes a major challenge to system-on-chip designers. Latency-insensitive design (LID) has been proposed as a "correct-by-construction" design methodology to cope with this problem. In this paper we present the design and implementation of a new class of interface circuits to support LID that offers substantial performance improvements with limited area overhead with respect to previous designs proposed in the literature. This claim is supported by the experimental results that we obtained completing semi-custom implementations of the three designs with a 90 nm industrial standard-cell library. We also report on the formal verification of our design: using the NuSMV model checker we verified that the RTL synthesizable implementations of our LID interface circuits (relay stations and shells) are correct refinements of the corresponding abstract specifications according to the theory of LID.